Three elderly people have died in Spain from suspected carbon monoxide poisoning after using a generator during the country`s nationwide electricity blackout yesterday, emergency services have said.

Police said the bodies of the 3 were found at a home in Taboadela, a town of around 1,500 residents in the northwestern region of Galicia alongside a domestic generator used by one of the victims to power an oxygen machine, regional emergency services said in a statement.

Emergency services workers detected "a high concentration of carbon monoxide" inside the house.

Spanish media also reported that a woman died during the blackout in a fire caused by a candle in her flat in Madrid.

The reports of deaths come as the European Commission said the EU will learn lessons from the blackout of an "unprecedented magnitude" across the Iberian Peninsula a day earlier.